A growing need exists for a practical system of identification for use in various specific applications to segregate counterfeits, imitations or fakes from genuine articles. Regarding commercial products, several indicators suggest that ever increasing numbers of fakes are appearing in a wide variety of different merchandise lines. The piracy of recorded material, e.g. phonograph records, audio tapes, and video tapes, has been a recognized problem for some time. However, the practice of marketing fakes now has grown to encompass many other products. Successful products bearing prestigious trademarks are copied in detail for fraudulent sales. Unfortunately, although legal remedies often exist to curtail the sales of such counterfeits, detection and enforcement often is difficult and expensive. To compound the problem, many fakes cannot be readily detected without careful study or inspection by a professional. In view of the various difficulties and the existing conditions, a considerable need exists for an economical, practical system to verify or authenticate genuine articles both in the interests of preserving trademark or brand integrity and protecting the public from fraudulent copies.
In the past, a wide variety of techniques have been used for trying to distinguish genuine articles from fakes. For example, finely printed labels have been used in the hope that counterfeiters could not make duplicates. However, present highly developed reproduction technology enables the duplication of very complex graphics with relatively little difficulty.
Individual serial numbers or other identifications have also been applied to products for the purpose of authentication. Yet, failing either complete cooperation from sales people, or a comprehensive detection and policing program, such techniques afford little protection against copies. As a result of such difficulties, product pirates have been relatively free to pick and choose from a current group of successful products that could be copied, the fakes to be sold on a global scale with relative impunity.
In addition to commercial products, authentication is important in a variety of other applications as for commercial paper, identification cards, documents of value, and so on. As disclosed herein, the system of the present invention may be variously implemented to authenticate a wide range of subjects, including people.
The present invention is based on recognizing that an effective system of authentication can utilize a device with an obscure random characteristic. The system also recognizes that objects with such characteristics are readily available so that authentication devices hereof can be produced and used inexpensively, enabling selective investigation. For example, a producer can provide his full line of products with an authenticator, then limit policing activities to either sample groups or those select, very successful products that are most likely to be copied.
In operation, the present system employs select physical phenomena that characterize objects. Each phenomenon is measurabe, but not practicably duplicable. Consider an example. The pattern of translucency variation in a sheet of ordinary bond paper may be seen by exposing the sheet to back lighting. That complex and random pattern of varying translucency is measurable but not practicably duplicable. Of course, such a randomly occurring pattern can be altered, for example, as by adding printing; however, the random character of the non-printed portion of the medium cannot be duplicated by a practicable effort. The present invention is based upon utilizing such a medium having such a measurable but not practicably duplicable characteristic for identification. Note that the characteristic being considered occurs randomly in nature, or in the production of a medium (without control) to provide a basis for identification data. such a randomly occurring characteristic is distinct from the operation of printing or otherwise designating a medium with a randomly generated numeral or similar data. It is the inherent random character of production or nature in a medium that is measurable but substantially unduplicable.
To consider another example, random variations in the naturally resulting reflectivity of a medium may be used as a measurable, but not practicably duplicable characteristic.
The medium may, for example, comprise: part of a product, part of a tag attached to a product, part of an identification device, part of a document of value, and so on. As a further aspect of the present discovery, the system may be implemented so that only a portion of the medium is utilized, and the location of that select portion is preserved in secrecy along with the measured characteristic.
In accordance with one technique of the present invention, a reference medium is sensed or measured to provide electrical reference signals representative of the select random pattern that is characteristic of the medium, but not practicably duplicable in a similar medium. Confirmation of that specific medium then involves another sensing of the medium and a comparison with the results of the original sensing.
In one exemplary application, reference signals identifying a pattern and its location are cryptographically encoded and recorded on the medium to provide a self-contained tag. Pursuing such an example in more detail, assume that the physical medium of the authenticators comprises bond paper. A defined area of each sheet of paper has a specified pattern of selected locations. Based on the characteristic of that pattern (and its location), reference signals are generated to be encoded and associated with the sheet, e.g. printed or otherwise recorded, as on the sheet. To authenticate such a sheet, the system of the present invention senses it to again detect or measure the selected pattern of authentication signals. The fresh signals are then compared to the recorded reference signals previously developed from the pattern. Coincidence of the signals indicates the sheet to be genuine.
As disclosed in detail below, the system hereof may be variously implemented using different media and techniques. For example, the location of the random pattern of concern may be visually obscure and can be cryptographically encoded by a computer apparatus. Also, the characteristic reference signals can be variously stored for future comparisons. Some or all of such signals might be kept on a list, or cryptographically encoded and recorded, in memory, or optically or magnetically on the authenticator media.